diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9ccef26..00974ca 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -60,7 +60,7 @@ jobs:
         run: sudo apt install ccache ninja-build
         if: matrix.os == 'ubuntu-latest'
       - name: Build
-        run: NINJA_FLAGS=-v make package LLVM_CMAKE_FLAGS=-DLLVM_CCACHE_BUILD=ON
+        run: NINJA_FLAGS=-v make package LLVM_CMAKE_FLAGS=-DLLVM_CCACHE_BUILD=ON DEB_ARCH=amd64 TAR_MACHINE=linux-amd64
         shell: bash
       - name: Run the testsuite
         run: NINJA_FLAGS=-v make check RUNTIME=wasmtime
@@ -168,6 +168,22 @@ jobs:
 
       - name: Run docker_build script
         run: ./docker_build.sh
+
+      - name: Cross-compile for ARM64
+        # Hacktastic cross-compilation step: build and install an ARM64 LLVM,
+        # reusing everything else we built using the native toolchain.  Once
+        # GitHub provides ARM64 runners to open source projects (planned for
+        # second half of 2024) we'll be able to build natively and avoid this
+        # step.
+        run: |
+          docker run --rm \
+            --user $(id -u):$(id -g) \
+            -v "$PWD":/workspace:Z \
+            -v ~/.ccache:/home/builder/.ccache:Z \
+            --tmpfs /tmp:exec \
+            wasi-sdk-builder:latest \
+            bash cross_build_arm64.sh
+
       - name: Upload artifacts
         uses: actions/upload-artifact@v4
         with:
diff --git a/Dockerfile b/Dockerfile
index adddd02..b0ff1e1 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -18,6 +18,8 @@ RUN apt-get update \
   python3 \
   git \
   ninja-build \
+  gcc-aarch64-linux-gnu \
+  g++-aarch64-linux-gnu \
   && apt-get clean \
   && rm -rf /var/lib/apt/lists/*
 
@@ -31,7 +33,8 @@ ENV PATH /opt/cmake/bin:$PATH
 ENV RUSTUP_HOME=/rust/rustup CARGO_HOME=/rust/cargo PATH=$PATH:/rust/cargo/bin
 RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | \
   sh -s -- -y --profile=minimal && \
-  chmod -R a+w /rust
+  chmod -R a+w /rust && \
+  rustup target add aarch64-unknown-linux-gnu
 
 RUN groupadd -g ${GID} builder && \
   useradd --create-home --uid ${UID} --gid ${GID} builder
diff --git a/Makefile b/Makefile
index da92c1e..accb151 100644
--- a/Makefile
+++ b/Makefile
@@ -283,8 +283,8 @@ package: build/package.BUILT
 
 build/package.BUILT: build strip
 	mkdir -p dist
-	./deb_from_installation.sh $(shell pwd)/dist "$(VERSION)" "$(BUILD_PREFIX)"
-	./tar_from_installation.sh "$(shell pwd)/dist" "$(VERSION)" "$(BUILD_PREFIX)"
+	./deb_from_installation.sh $(shell pwd)/dist "$(VERSION)" "$(BUILD_PREFIX)" "$(DEB_ARCH)"
+	./tar_from_installation.sh "$(shell pwd)/dist" "$(VERSION)" "$(BUILD_PREFIX)" "$(TAR_MACHINE)"
 	touch build/package.BUILT
 
 .PHONY: default clean build strip package check
diff --git a/cross_build_arm64.sh b/cross_build_arm64.sh
new file mode 100755
index 0000000..0267518
--- /dev/null
+++ b/cross_build_arm64.sh
@@ -0,0 +1,9 @@
+#!/bin/sh
+set -ex
+
+rm -r build/llvm build/llvm.BUILT
+NINJA_FLAGS=-v make strip LLVM_CMAKE_FLAGS="-DLLVM_CCACHE_BUILD=ON -DCMAKE_C_COMPILER=aarch64-linux-gnu-gcc -DCMAKE_CXX_COMPILER=aarch64-linux-gnu-g++ -DCMAKE_CROSSCOMPILING=True -DCMAKE_CXX_FLAGS=-march=armv8-a -DCMAKE_SYSTEM_PROCESSOR=arm64 -DCMAKE_SYSTEM_NAME=Linux -DLLVM_HOST_TRIPLE=aarch64-linux-gnu"
+CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc cargo install wasm-component-ld@0.5.0 --root "$(pwd)/build/install/opt/wasi-sdk" --target aarch64-unknown-linux-gnu
+mkdir -p dist
+./deb_from_installation.sh "$(pwd)/dist" "$(./version.py)" "$(pwd)/build/install/opt/wasi-sdk" "arm64"
+./tar_from_installation.sh "$(pwd)/dist" "$(./version.py)" "$(pwd)/build/install/opt/wasi-sdk" "linux-arm64"
diff --git a/deb_from_installation.sh b/deb_from_installation.sh
index 2699c81..779abed 100755
--- a/deb_from_installation.sh
+++ b/deb_from_installation.sh
@@ -27,13 +27,17 @@ else
     INSTALL_DIR=/opt/wasi-sdk
 fi
 
+if [ -n "$4" ]; then
+    ARCH="$4"
+else
+    ARCH=$(dpkg --print-architecture)
+fi
+
 if [ ! -d $INSTALL_DIR ] ; then
     echo "Directory $INSTALL_DIR doesn't exist. Nothing to copy from."
     exit 1
 fi
 
-ARCH=$(dpkg --print-architecture)
-
 rm -rf build/pkg
 mkdir -p build/pkg/opt
 mkdir -p build/pkg/DEBIAN
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 9fda470..30ec63e 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -8,7 +8,7 @@
 # separately.
 FROM ubuntu:22.04 as dist
 
-ADD dist/wasi-sdk-*.*-linux.tar.gz /
+ADD dist/wasi-sdk-*.*-linux-amd64.tar.gz /
 ADD dist/libclang_rt.builtins-wasm32-wasi-*.*.tar.gz /wasi-sysroot-clang_rt
 
 # Move versioned folder to unversioned to using bash glob to allow
diff --git a/docker_build.sh b/docker_build.sh
index 050862f..6343c27 100755
--- a/docker_build.sh
+++ b/docker_build.sh
@@ -8,6 +8,7 @@ docker build \
 
 echo "Building the package in docker image"
 mkdir -p ~/.ccache
+arch=$(dpkg --print-architecture)
 docker run --rm \
     --user $(id -u):$(id -g) \
     -v "$PWD":/workspace:Z \
@@ -15,4 +16,4 @@ docker run --rm \
     -e NINJA_FLAGS=-v \
     --tmpfs /tmp:exec \
     wasi-sdk-builder:latest \
-    make package LLVM_CMAKE_FLAGS=-DLLVM_CCACHE_BUILD=ON
+    make package LLVM_CMAKE_FLAGS=-DLLVM_CCACHE_BUILD=ON DEB_ARCH=$arch TAR_MACHINE=linux-$arch
diff --git a/tar_from_installation.sh b/tar_from_installation.sh
index 7d09432..ade0fcc 100755
--- a/tar_from_installation.sh
+++ b/tar_from_installation.sh
@@ -19,14 +19,18 @@ else
     INSTALL_DIR=/opt/wasi-sdk
 fi
 
-case "$(uname -s)" in
-    Linux*)     MACHINE=linux;;
-    Darwin*)    MACHINE=macos;;
-    CYGWIN*)    MACHINE=cygwin;;
-    MINGW*)     MACHINE=mingw;;
-    MSYS*)      MACHINE=msys;; #MSYS_NT-10.0-19043
-    *)          MACHINE="UNKNOWN"
-esac
+if [ -n "$4" ]; then
+    MACHINE="$4"
+else
+    case "$(uname -s)" in
+        Linux*)     MACHINE=linux;;
+        Darwin*)    MACHINE=macos;;
+        CYGWIN*)    MACHINE=cygwin;;
+        MINGW*)     MACHINE=mingw;;
+        MSYS*)      MACHINE=msys;; #MSYS_NT-10.0-19043
+        *)          MACHINE="UNKNOWN"
+    esac    
+fi
 
 if [ ! -d $INSTALL_DIR ] ; then
     echo "Directory $INSTALL_DIR doesn't exist.  Nothing to copy from."